I have kept redlines now for many years. I actually sell them on occasion when I am at fish events and doing room sales or am in the vendor room. I also have them in my 150 gal tank with my big clown loaches. These fish will get to be about 5 inches when fully grown. They will also vary in quality. A lot of what now reaches the market are farmed fish rather than wild caught and these farmed ones often do not compare in coloration etc.
They do work nicely when kept in groups, but I think a 75 is too small for 10. Think more like half that number. They are pretty active fish and will generally only squabble among themselves and do not tend to bother other fish. However, their active nature can upset/stress other smaller more docile fish like guppys. Redlines also like somewhat cooler temps. I confess that I tend to keep them too warm which I know is likely to shorten their life despite my providing clean water and good food for them.
I have a batch I purchased to grow and sell and I have noticed a few of them have slightly deformed tails, the black and yellow striping is not quite right on the top fork of the tail. I attribute this to the farming techniques. They are not so easy to find in the wild any more.
The first time I saw pictures of this fish for sale on AquaBid, I though they looked like SAEs on LSD. The colors are amazing when they are adults. Of course I had to have them and I paid up for them. I have never been without a group since. Some of the best information about these fish in the wild can be found here where the well known Indian fish keeper, Madan Subramanian details his trip to collect them in the wild. It has a lot of pictures and the information about them will surprise most. They behave differently in the wild than in our tanks. http://indianaquariumhobbyist.com/community/modules.php?name=News&file=article&sid=86&mode=thread&order=1&thold=0
The first information I found on these fish was in an article where the author visited Madan in his home and saw these lovely fish in his tanks. I cannot find this article now, but there is still good info out there by Madan as in the above link..
I sell these fish for about $12 as singles and a group would be less. I have never shipped this species as I usually sell them in person and I do not spawn them (most of what I sell are fish that spawn in my tanks). However, WetSpot in Portland sells them and ships them as well. They currently have 6 tank raised 1.75 inchers for $75 plus shipping here http://www.aquabid.com/cgi-bin/auction/auction.cgi?fwcyprinids&1458319810
I have gotten these fish from a retail seller who buys from their wholesale operation and I was very satisfied with the fish. I got them a couple of years back, I do not think they were TR back then. They were my second group. I know for sure my first group were wild.
As for how they would work with bristlenose...