What do you like for your bass bug and mouse patterns? Nature's Spirit sells "spinning hair" which looks like it is from the regular hide versus their "deer belly hair" which is belly hair dyed.
Also, Pat Cohen's site looks like it has nice spinning hair.
Any other sources?
I, personally, use different hair for something like a mouse vs a spun/stacked bass bug. For a spun or stacked bug like a popper or diver, I use deer belly hair. I have no business ties to Pat Cohen, this is merely my opinion with no strings attached, the hair I have gotten from Pat is night and day better than anything else I have ordered. My advice, if you're going to tie a lot of deer hair bugs, avoid the frustration and buy your belly hair from Pat. I have found through a lot of experience and frustration that quality of materials makes a big difference. Use the right stuff and your results are going to be better (good hair, the right thread, the right hook, etc...). I have had good patches of hair and bad patches when not buying from Pat. If you get a patch of really short belly hair, it's a lot harder to work with and I end up chucking it in the trash can. I have not (knock on wood) had a bad patch from Cohen yet. It's longer hair, easier to work with, and the colors are great.
When I'm tying a mouse, I use belly hair on the belly of the mouse (usually white), but use premo strip body hair for the top of the mouse. But, it depends on how you choose to tie them. If you do them more like Chris Helm did his mice, you can use belly hair for the whole thing because you'll trim away all the tips on the fly. I keep the hair tips for my mice patterns, so I like the more natural look of body hair for them. A premo strip will last you a LONG time, too. I think they are around $12-13 but I have some I have tied on for multiple years.
Here's what Helm's mice look like: