The BBC model B has many different keyboard types. On this video, I am changing a Futaba simplifed liner type 1 key base. This is quite a common one and although it requires a bit of soldering iron work, its not to bad to replace.
I bought my replacement key on eBay from this company http://www.retroclinic.com. No affiliation, bought with my own money but have to say it was a quick delivery and a good quality product.
I'm now on Patreon, if you like what I do and want to support me head on over to patreon.com/billfixeseverything
Music by C4C - Bright Side - https://thmatc.co/?l=2CCAC558