Walter is correct. The Tyler T #2 is correct for the I frame and the very early J frame (as the Baby Chief). The Tyler #1 is the correct one for the later, post 1955, I believe, J frames.
You mentioned the Terrier. The early Terriers were indeed I frames, but the last ones made were J frames, IIRC. So if they make a T Grip to fit an early Terrier, it will fit your I frame, but if made for the later ones, it might not fit exactly, as it will be designed for the J frame.
The only problem is finding the #2s. Around here they are outnumbered by "hen's teeth"!!! I've found exactly two of them on eBay in the last year, and missed the auction on one of those.
Here is a relatively recent manufacture Tyler #2 on my 1923 .32 Hand Ejector. Not period correct, but provides a wonderful feel. I would highly recommend one, if you can find it!!
PS...you can see the zip code on the address, so it is possible to date from that, and the "anodizing" style of lettering. Some are stamped, others lack the zip, there are experts who can help to find the older ones. But that is not a field that I know much about. I was lucky to even find a number 2!!!
Edit: I went to the Tyler T Grip web site, and it looks like they have kept the same numbering system that they used to have. So if you order the one that they say will fit the Terrier, it is the #2, and should fit your gun.
Best Regards, Les