Hi Will - I desired a copycat more than anything else.. but simply couldn't afford one in my teens / early 20s..
Then the Roland Space echo was released and adopted by Dub reggae sound systems..
But that was even more expensive..

I've made do with echo / delay FX pedals ever since.

I did find 2 Watkins side by side on the floor of a 2nd hand shop in Taunton about 16 years ago..
I think they were both the later solid state versions, but the wife was with me, and even if she could be persuaded,
there was no guarantee if or for how long they would work.

From 1977, our keyboard player performed the synth cosmic space echos with a big box early ananlog bucket brigade chip delay..
dunno what it was though..

Back in the 70s us provincial guitarists were self taught and clueless about gear technology.
None of today's tutorial industry and college music tech courses existed for us back then..

My dad got me that AC30 for fifty quid off 'a bloke' he knew
and impressed me and my mates by saying it was a Beatles Amp..

When it suddenly died he also got suckered in by the HH amps futuristic green glowing control panel
and signed up for the HP...

Plus Wilko Johnson used one..

I persevered with that amp from 16 to mid 20s, but could never get a decent sound from it.
It was certainly impressively loud, but the tone was too hi fi sterile
when I wanted the sound of The Who's early records..

In the mid 80s I donated mine to a west country music co op..

These days they are apparently very collectable legendary vintage amps...?????? 🙄