If you look through the 10-10 IPLs you may be able to narrow down the change over. I tried to fit a low filter on my saw and I don't believe it was even wide enough to cover at the base, you might be able to 3D print an adapter.
My 10-10s (non-Super) have the high filter:
View attachment 461203 Part number 66774
The Super 10-10s look to have the low filter:
View attachment 461204 Part number 69922
The later Pro Mac 10-10 (what ErnieG got) uses the same low filter:
View attachment 461205 Part number 69922
The Pro Mac 10-10s looks to have a similar low filter, but different part number, possible same filter just newer part number:
View attachment 461206 Part number 216685
If you get a 10-10 with the low filter, let me know, I have a new low filter I don't need.
It looks like (looking through the IPLs) all of the right-hand pull start 10-10 (1967-1970) have the high filter and the last two years of production (1971-1972) they swapped the pull start over to the left hand but continued to use the high filter. All of the Super 10-10, Pro Mac 10-10 and Pro Mac 10-10s all used the low filter.