Ah, finding a sight rail might not be as easy as I thought then...
Multishot! You'll want to buy her an LP50 Compact, then... this is getting a bit heavier, and more expensive.
This chap has made rails for the LP50: http://www.airgunnation.com/topic/wt...l-for-red-dot/
OK, he's in the USA, but I can't see it costing more than 50 or 60 quid to have a short bit of rail made up for a Steyr pistol - if indeed that's what the lady wants?
edit: LP50 Compact, 983g plus sight & rail: http://www.steyr-sport.com/en/steyr-lp-50-compact
If one can't be bought off the shelf, I'd ask AJP or Shaun @ ISP about the rail.