Have you checked out FoRender? http://forender.aca.ca/
The Sci-Fi section might be of interest here:- http://forender.aca.ca/market/all-categories/sci-fi-weapons?limit=50
If you are interested then it might well be worth signing up as he often e-mails discount codes for up to 35% off (excluding new items). I only get about 1 e-mail a month so he doesn't clutter up your in box either. (Disclaimer, I have no connection with the site). He does not include DS mats but a few minor tweaks to the surface settings usually improves the look in DS if that is your software of choice.
I'll have to get round to reinstalling some of his weapons as I haven't got round to putting them back yet after a major system clean up & reinstall.
Sorry about the delay, UK based so was just powering down last night when I posted above