I can't believe you guys don't recognize those Jay Scott plastic pearl grips! They made black and white pearl, stag, and ivory out of PLASTIC with the wood backers.
Google em!
jay scott grips - Google Search
The 44 Frontiers I have owned usually lack a caliber mark.
The Op's gun is refinished, possibly by the Factory.
I can't tell from his pic if the extractor is blue or white.
Here is a neat old original 4", not cut. The grips are original and numbered to the gun. It had no caliber mark even though it is #7252. I do not remember if I checked the extractor for a serial number, but it is white.