You might have a tough time here. . .
I've been looking to up my shoal of Kuhli for a year now, but they've been really difficult to find. In my experience every shop that used to carry these fish as a normal part of their stock (which was most of them!) has been having a lot of trouble getting them in at all. When they do get them in, I've been seeing a lot of 'bad batches,' where the entire shipment comes in with some mysterious illness and don't make it. It's been a huge concern of mine for quite some time now.
P.Kuhli and P. semicincta do not
breed in captivity, and because of this the fish you find for sale are almost exclusively wild-caught... and not farmed like most of our ornamental fish are. I'm not really sure what's going on with with the wild stock, but based on info I've seen here and on other forums, it doesn't seem to be just a local thing. I suspect that the reasons they 'don't ship well' is that they've just undergone a long voyage from their natural habitat to the shop, and then to your home - with many stops in between without a chance to de-stress and become acclimated to things. They're tough little fish, though, and it used to be that they'd come through well despite the odds.
One thing worth trying if you haven't already is to go to any local fish shops you may have in your area and ask them if they're able to put in a special order for you. Most LFS are willing to do this, though you may have to pay for the fish in advance, or put a deposit down. But I had several shops ordering these fish for me for almost an entire year before a good shipment came in - and those turned out NOT to be the correct fish, but rather a dwarf version (a nice shoal of which are now happily living in my tank!)
I'd say that if you want P.kuhli or P.semicinta, you might be best off to go ahead and pay the shipping fee to get them shipped, it may be your best bet at this time, if you can't find them locally. Be sure to go with a reputable seller. The only recommendation I can give you based on my experience (and those of others I've spoken with) is a shop based in Oregon called The Wet Spot.
Though you'll pay around $50 for overnight delivery, they do have a live arrival guarantee, and they treat all of their wild-caught specimens and keep them in QT for a period of at least a month before shipping. In my opinion, if you have
to order these fish, it's well worth it to go with them.
ALL THAT SAID. . . looking at your siggy, these fish may not be a good match for you. P.kuhli and P.semicincta are on the small side, but they grow to be around 3 inches or so. In addition to this, they are a VERY
lively fish when properly kept, and they really do need more room than what you would have available in a 10g tank. I would say a 20 gallon long (or a 29 gallon - same footprint) is the minimum that they'd truly be happy in.
The other thing to consider about these wonderful fish is that they're very social and true shoalers. I've read the minimum in a few places listed as 3 fish, but in truth, and based on my experience, if you want to see them happy, comfortable, and active, a shoal-size of 6 should be the minimum that you purchase. They also require a soft-water, well-planted, and matured tank set-up with a sand substrate (gravel can damage their sensitive barbels and soft underbelly, and so should be avoided with this species)
An alternative that you may want to look into - if you can find them - is the dwarf species of loach called Pangio cuneovirgata. These guys would be perfectly in a 10g setup, and you could easily put a shoal of 6+ with an upper-dwelling fish without overstocking. Unfortunatley. . . these might prove to be even more difficult to locate!
I'm sorry to be the bearer of bad news, I hope you find what you're looking for! The eel-like loaches are wonderful fish, and absolutley one of my favorites! Good luck!