The clue is the "A" after the 440.
The original Mitchell Match reels were blue in colour, and had "Match" engraved on the gear case, with no number.
The gearing inside the early reels was good quality Brass.
When they added the "A" they also added a seal around the gear case and cheaper zinc gearing, I think they only fitted the seal as the case wasn't as well manufactured.
Incidentally there was an even quicker retrieve model, the 840 Match with really high speed gearing, which only resulted in mega line twist.
Here's a proper one.....
MITCHELL MATCH REEL. GOOD CONDITION. | eBay
And a better proper one...
VINTAGE MITCHELL MATCH FISHING REEL NOT 440 | eBay
You might notice the counter weight on the spool housing opposite the "dab" mechanism, which wasn't fitted to the very early (Pre '75) models
If you like I could put up some pics of my 2 Matches & their gearing tonight?
Andy