Yeah, I've found some time to do a little research and it looks like they may be standardized, so I just need to get ones that have a 3.5mm plug on it.
I actually have one from an old Hauppauge TV tuner card, but it is 2.5mm, so will not fit (plus it also has a IR receiver on it too, so not sure if it would work anyway).
Looks like the $3.00 ones on eBay should be fine.
Please let me know if anyone has had trouble with using generic IR Blasters on the Replay.
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