"Well, I didn't get many responses here but I tried my luck anyway.
This was eventually authenticated by JSA, certification number BB01797.
Just in case somebody is looking for genuine Harrison Ford autographs, here is an example."
"Can I ask how you feel about these three signatures. They were all authenticated by either PSA/DNA or JSA. The last one even got a grade of 10 but I feel like the C^^^^^^y part looks off compared to other signatures I've seen. Thank you."