Possibly as much as another $200!
From page 12 of Catalogue of Manmade Material on the Moon (found here)
From http://www.jeffersonspacemuseum.com/apollo-15
About the Bill
The crew of Apollo 15 took along \$2 bills and \$20 bills within their pilots preference kits (PPKs). This bill is one of the 50 flown US two dollar bills which made it along on the mission in the command module Endeavor with Al Worden, and remained in lunar orbit while Dave Scott and Jim Irwin explored the lunar surface. Another package of bills was flown to the lunar surface, but were unfortunately left there by mistake -- leaving a number of extremely rare \$2 and \$20 bills that have spent the last 40+ years on the lunar surface. The Apollo 15 crew would later become embroiled in a scandal involving flown postal covers, which would impact all future US manned flights in terms of what could be carried in a PPK. By 1973, currency and coins, which could be commercialized on the secondary market, were banned by NASA from being taken along on US space flights -- forever altering the tradition on post-Apollo flights. (Even official NAA flight certification dollars were changed to flown certificates on later flights to comply with this regulation.) After Apollo, only bills flown via Russian Soyuz or private commercial flights (such as SpaceShipOne) would add to the population of space flown \$2 bills.
