^ Less than 5V, so if they work into DR2d, they should work into PR-2, maybe better. Yeah any of the miniature ATs (and the SoundProfessional rebrands of them)
Any miniature DPA straight in.. meaning the directionals as well as the omnis, but that's out of budget except maybe used. Any regular sized DPA with the micro-dot output amplifier, but that's WAY out of budget. I'm curious about the small Neumann cardioid (KK14 I think) that some have modified to work with a 5V supply but that's probably also over budget.
The regular goto battery-box-powered small mics should all work: AudioTechnica, ChurchAudio, SoundPros, SonicStudios, Sennheiser, homebrewed Panasonic/Primo/Knowles capsules, etc, as well as small mics less common ones in the taper world, as long as they can be configured to work into a 2-wire input and operate correctly on 5V, which will be most of them. Hmm.. Sony, Shure, others I can't recall off-hand.