I paid for my ZTE MF626 54,95Eur and this is one of the cheapest modems. A modem from A1 costs 59,95 and other provider have the same prices.

Recommend models, providers and prices (€):

ZTE MF626 I Yesss! I 54,95,- (simfree)

Huawei E1150 I Drei.at I 54,90,- (simlocked)

Option iCon 225 I Telering.at I 59,- (simlocked)