http://vectrex.playntradeonline.com/They are running a Black Friday sale on the Vectrex Multicart. Its the
Lite version which means you'll have to hack up another game (or find a repro shell) to fit it in, but for the price seems reasonable. (about $38 after conversion, includes shipping)
I've been meaning to order one for ages but finally bought this one. There's a few different ones floating around at this point but the game list on this seems fairly good with all of the original releases as well as some of the more recent homebrews.