From
Natsume Maya:
"More release details for the
Futatsu no Spica (Twin Spica) DVD Box to be released on 22 July 2004: catalogue number KIBA-91066, price 31,290 yen (including tax). As previously stated, it'll contain all 20 episodes."
Considering how expensive R2s typically go for, that's a pretty good price for a 20 episode series.