I think the problem is that there is not much money to be made and alot of risk and time involved.  Anyone that would have a store would just be buying bulk from Lik-Sang.  If a US store charged $20.00 more per unit everyone would just order from LS directly.  If a US store charged less, It wouldn't be worth doing.  There are risks as what happens if you get some dodgy units?  you have to ship back and forth and so on.
I was thinking about doing it too but decided against it.  Although one reason is that I can't program HTML to do a website.  I would have been able to do the GP32 side well as I can do volt mods, Glass screens, button tune-ups etc.  All of mine would go to 166 as any lame units would have automatically been modded by me.