you can try and ask tinlong, he may have some leftovers from last GB (there is also a thread on DT)
imav also sold some lately, dunno if they are all gone
I'm not sure you'll see a big difference compared to the pure appart from the switches
If you really can't find one, I'll sell mine as soon as I got the GH60 (could be a long wait though)
and Welcome to GH I guess! ^^