I have recommended Pedro plastic tire tools as well because of their strength relative to Park style or other
varieties of plastic tire tools. Their width may make use on a tight 520 sized wheel a bit problematic compared
with 622 sized wheels. Metal tools will score aluminum rims and raise sharp ridges on the rim, not a good
idea. I tried some plastic tools molded around a metal insert that worked for awhile but even those made a
mild dent in the rim edge, sans any sharp edge, but the plastic 'hook' that goes under the bead flattened out
after a year or so making them useless. Any tire tight enough to make insertion of one plastic tool difficult
means trying to get a second tool in will be impossible for most of us.

This tool https://www.nashbar.com/tyrekey-tire...rekey/p1007690 "might" be helpful, although
the product video showed its use on a tire that could probably have been installed by hand, but the tool looks
promising. Both Spin Doctor and Silca make reinforced tire tools that look to be narrow and strong. I have
used none of these.

One addition to your kit would be a small container of soap concentrate, which applied to the
rim and the bead facilitate removal but don't solve the problem of the bead repeatedly popping off the tool in
the first place.

Finally, since your tire selection is so poor, you might consider whether a 456 or 540 sized wheel could be fitted
as this might give you some more tire options. Depends on your fork/brake adjustability relative to the rim.