Well, both sources were so nice to send me the apk files directly. Triposo installed just fine, whereas WikiSherpa balked at me because of some Google Maps files missing. Actually installing Google Maps didn't help, so I ultimately came across this post:
I have the missing files now, and all I need to do is copy them to my device, but the method described didn't work for me (keep getting a "no space left on device" error). So that's where I'm stuck now.