The second easiest thing would be to post news asking for ROM images. There are probably quite a few CoCo maniacs out there who have these available on-line, and would happily e-mail you an image. There is a CoCo mailing list server at Princeton that you might try. But be aware that those ROMs are still under copyright protection; copying them is illegal, and I don't personally recommend this.
The hardest thing to do is get them from me, because I don't have the ROM images on-line, and don't ever plan to make them available on-line, because (as noted above) that would be a copyright infringement. I do have a couple of extra ROMs that I could send, but you would have to pay for the postage costs, which might outweigh the cost of an entire CoCo. To make things worse, I am very busy, and it might take weeks for me to get around to digging out those chips and getting them in the mail. Having said all that, if you really need it, let me know, and we'll arrange it.
If you do get a whole CoCo, rather than just an on-line image of the ROMs, there is a simple program (maybe three lines of BASIC) out there for extracting the ROM image that is needed by the emulator. I seem to remember seeing this with the emulator itself, so you may want to check wherever you got that. If you have trouble with that, let me know, and I'll help you find or re-create it. (Not being a copyright lawyer or anything, I think it is legal to use the ROM image in the emulator, as long as you actually own the ROM itself...)
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