btbowhunter,
You might want to consider making your own remote caller.

They're easy to make, made this one for under $140 buying the stuff off of E-bay & Amazon, and if I had been more patient it probably would have come in cheaper. It consists of a Nady 151VR-LT Transmitter & receiver, a used Rio 600 mp3 player, and a Speco SPC-5P speaker and a cardboard tube. Also there is free software to convert the cassette tape calls to mp3s.
Happy to get into more details, if interested.
Bob