Thanks for this. 40s and starting to have pain in the big toe joint. Getting some better shoes and spacers as a result. Seriously, thank you!
Weird timing - I saw some on Amazon yesterday (clicked in to see if there was another three things I wanted in order to get 5% off ... but it was all bizarre tat, who wades through all that, or finds four useful things anyway, for 5%?) and wondered what on Earth they were for, I didn't realise this was/could be an issue - certainly not commonplace enough that there was a product for it anyway.
For most cheap imports like this, I've found eBay is wonderful.
My girlfriend wanted toe spacers and I found the exact same no-name pair on eBay for $4, compared to $10 on Amazon.