In my year working at an LFS, I never saw a relatively small one. Certainly not the size you can find regal blues at...most were on the larger size.
And they are very very delicate. I know you have asked this before. They REALLY ARE delicate. You will put it in a tank that is small, with fish that may pick on it, then try to move it to a larger tank, which won't be as mature...
These are all stressful things, and these fish do not survive stress well.
Why not just wait until you get the bigger tank, get it nice a mature (AT LEAST 6 months, min) so that you have a better chance to keep one alive?
I know you want one, but how badly? Do you want to kill one? Because, really, odds are very good it would not survive long in the 60. The majority of them do not. If it did, it would be, IMO, atypical.