A decent LBS should be able to put in a sleeve that can then be threaded to allow you to refit the derailleur. Dropouts can also be bent backwards using an alignment tool. You don't want to do it too often but it should cope with being bent back.
Whereabouts are you based?
@andyp started
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A decent LBS should be able to put in a sleeve that can then be threaded to allow you to refit the derailleur. Dropouts can also be bent backwards using an alignment tool. You don't want to do it too often but it should cope with being bent back.
Whereabouts are you based?