Betty Spital is easily found on Amazon, courtesy of The Thoughts of Betty Spital: Pensioner, Activist and Radical Granny, but that's written by a Christopher Meade. I'm pretty sure the Radical Pensioner who played our club at the start of 1989 was a middle aged woman.
To be honest I'm drawing a blank, both in the memory banks and on Google. Maybe Betty Spital was Christopher Meade. I'm sure someone will tell me.
The illustration on the poster is, of course, Mrs Brady Old Lady from Viz, but you knew that. Viz, you will recall, was very big in 1989, being only 10 years into people telling it that it wasn't as funny as it used to be. In December 1989 it became the 2nd best selling magazine in the country, second only to Radio Times, selling over a million copies. Did I mention my strip, Tarquin Hoyley He Has To Go To The Toilet, was in it a couple of times? You'll find them in the Big Pink Stiff One book. I don't get royalties.
As for googling Post Glasnost, forget it. The best I get is a comedy series from 1991 called Sleepers, a "post-glasnost comedy" starring Warren Clarke and Nigel Havers. Probably brilliant, but most likely not the comedy act that graced our above-the-pub smokey Leicester club in the frozen wastes of January 1989.