Thanks for the suggestions - I wouldn't say Lehle and Source Audio ones were in the "affordable" bracket though as I looked them up and they were about £300 and £200 each! The Mission Engineering one was a little more cost-effective, but I ended up going to Anderton's on Friday (getting stuck in ludicrous amounts of traffic each way, meaning my travel time was four times as long as the time I spent in the store yay

) and grabbing an EHX one new for the princely sum of £65, good value and comes with a year warranty so if it pops it's clogs in the meantime I can have it replaced FOC.
While I was there I also picked up a Shubb C4 vintage radius capo, as is turns out none of the 3 I had were matching the Jag neck and it explains the out-of-tuneness that was happening when using them, and for songwriting I use them a lot (basically I have a different song or two written in fret positions 1-5 for the whole originals band album I'm working on) so it's kind of important. Took me a long time to figure that one out
It's fairly lightweight, the sweep is small but accurate so foot tremolo is a thing again. Also it's passive so I got to pull a big 12V wall wart off of my organ sim board mains extension lead, and has a little switch to go from 25K to 250K. Construction inside is simple but good, blue PCB used throughout and the design is dated 2017 so it's relatively new as a product, not some ancient design as I was expecting.
Downside was having to mess around with patch cables again for ages to make everything fit as the input/output jacks on the EHX are way lower down. I start to remember why I used guitar multi-effects for literally a couple of decades - you don't have to worry about this kind of nonsense, fiddling with positions of mains adapters and patch leads, and in my case literally taking a meat cleaver to the oversized ends of the L-jacks to make them fit through the curtain holes on the pedal board.
