Nice piece - Harbridge doesn't turn up that often.
Extremely unusual to find cut glass pieces that genuinely had a frog/flower support, such double acts seem to have been almost exclusively the property of pressed glass.
I know Stuart did at least one 'pair' (a large wide cut vase) with accompanying frog, where the support carries Rd. 637674. Although the vase is without a No. I'm assuming it was 637675, since they're partnered in the Blue Book - however, the vase does carry the Stonier =S= mark, so probably a genuine pairing - and Bernard has commented that John Stonier sourced only from Stuart. There must be others, but they're certainly thin on the ground.
Apart from my Stuart example I don't recall seeing any other cut piece with a support, so although it's possible this Harbridge vase was born with a frog, the probability is that it's more likely the scratches were caused by a housewife's engagement ring or other cleaning implement.
I believe the company were producing for some considerable time after the '30's, but if the mark remained unchanged then perhaps not easy to be specific about a production date, but it does have a pre war look.
just goes to show that some backstamps can be the devil to find - it's easy to spend hours before finding them, and then again you can spend days and find nothing - or even invent something