A companion to the work already done with the Audio Technica BPHS-1, I'd already sourced a cheap foot switch from CPC at £11, plus the cable at £8 for a pre-terminated 3m (A longer version of the one used to make the -40db Attenuator cable for Outboard Audio from the Behringer Xenyx Mixing Desk. That switch went on Back Order till December, so I went hunting again and a bit more research into music foot pedals (I am not musical in the slightest)
There are many sustain pedals and effects pedals out there for Synthesisers and Guitars respectively, however the wiring wasn't ever given in the manuals, even though a number had a Polarity setting quoted. The one that looked good to me was the Boss (Roland) FS-5U Unlatched Foot switch. Now, this isn't £11 but it is a reasonable £29 from Amazon. The case is extruded Aluminium and has a robust foot switch, rubber base and Mono 6.35mm jack for connection into the Radio via the aforementioned RCA to Mono 6.35mm cable.
A number of tear downs of this switch appear on YouTube, so I got a look inside and it looked like I could do something with it to get foot PTT whilst using the headset.
The FT-2000 has a RCA PTT connection in the back, where the centre signal pin is grounded to the outer ring to get PTT.
The switch is actually quite comfortable to use and the PTT has been positive with no click, but a smooth changeover from the switch that feels like a quality item.
Recommended as a Foot Switch for the Yaesu Radio, especially if you have added a headset or want to keep you r hands free for logging. I guess you can go cheaper, but I think the price paid for the item, based on it's build quality and the feed back from the music community should mean this keeps working for a long time.