Ale named after me.

[Mad Doug Biker]

Blimey! You really have thrown yourself into the research, haven't you? Castleford would make sense; the 301 signifies West Yorkshire.
Most of the glasses I find seem to carry one of a very limited set of numbers: 323 or 324 (Gateshead), 478 (St Helens) or 64 (Newcastle on Tyne), all well known centres of glass production. Mrs Poacher will be furious if you rekindle my collecting instinct!

Just going on what I've read here and there.

As for numbers, I have found all of those except for 324 at the moment, but I have seen (and in some cases bought) several others on Ebay alone, such as numbers 2, 16, 18, 29, (64), 76, 90, 253, 301, 303, 317, (323), 387, 414, 418, 465, (478), 524, 542, 544, 562, 589, 881, 886, 1043, 1110, 2043 and 2139.
I'll let you and @classic33 work out what they all are if you are deperate enough!!

I am not saying I have bought them all, but I am moving, so will need glasses to drink from!!