IPv6 subnets are supposed to be super cheap. As an individual, through a RIPE LIR, I was able to get a /44 (2^20 /64 subnets), no questions asked. I have these tunneled into my home lab and a couple other locations. I realize my setup is unusual: I have my own ASN and am running BGP.
If you work with a RIPE LIR, they may be more than willing to help you, even if you are outside of Europe. You just need a "presence" in Europe, which can be virtual (a VPS counts.)
I am in the ARIN region but I did not want to pay the ARIN registration fees for an ASN. It was $550 + $150/year, so I went with a RIPE LIR.