I really like the Opsgear UMP folding kit you linked. The mag, stock, and shroud were all on my list to get. After that, I would only need the 8 or 10 inch Lapco bigshot, a supressor (gives it the MP5 silenced looked) and a remote line.

Edit: Actually, the mag, stock, and shroud sold seperately come up to like 195$. I don't like the front and rear sights (waste of $ in my opinion).
Thanks for the help!