Cheapest($) legacy deck

According to MTG stats, Glimmervoid is run in about 21% of Legacy Affinity decks, as a 2-of. Modem Affinity at 81% of the time as a 4-of. The reason is none of the Artifact lands are banned in Legacy. Mox Opal i'd say is a more important investment (and a more expensive one).

Lol well mine is shaped for modern instead of legacy but ima fix it for the legacy grand prix in Atlanta I'm so excited :3 anywho Mox opal will likely drop after October when scars cycles out not too much but make it that much more affordable and even if you end up buying more than a playset(like me XD) it's good trade fodder

Don't expect the price to drop. If anything I'd expect the price to rise as there'd be an even more limited number of them on the market