Whilst I have little doubt this handy but generic little board can be sourced elsewhere, I wanted the peace of mind of PiHut supplying, and delivery was rapid. I have not used this board for its usual arcade application; instead, I used it to create a Master System-inspired controller primarily for use with Raspberry Pi on Retropie, and occasional PC use. I desoldered the connectors on the board to save space and directly passed wires through the holes vacated. One great thing about this set up is the directional buttons use the Joy VCC Up Dn Lf Rt inputs meaning all remaining buttons aside from the 4 pre-allocated moder / turbo etc (which I omitted) are free for other uses. In total I have start / select / hotkey / 4x Action buttons / 2x shoulder buttons / 2x trigger buttons (matching PSX pre-analogue with the addition of hotkey for emulation menu access etc).
I have been looking at other options to achieve this such as a Pi Pico, and that will potentially make an even better basis at some point, but this set up is completely plug and play, no hassle, no programming, so for an amateur hobbyist like me, it's perfect. Now, if only there was a wireless version in future...