If you want her, buy her Jen. She's not really a rescue coming out of a pet store but heck remember my two biggest females were pet store dump offs (ex-pets literally dumped off at a local private pet store). As long as you do strict QT with her and check her out well, she may be a lovely addition to your collection one day.

Since the pet store is selling her on consignment I'd definitely tell them that you want any available information on this snake from it's past owner.