Okay, a word first about the technology here, because there are some real misunderstandings about speed guns. The ones you see on the TV are calibrated to take the average of the speed either side of impact with the surface, so you get a theoretical average of how quick the ball left the hand and how quick it was after pitching. These have, as I think I've probably bored some people by saying rather too frequently, been calibrated differently over the years - there was a period in the later part of the last decade where Sky took rather more of a reading before pitching which resulted in some bowlers being unreasonably labelled as rapid - so called "heavy ball" bowlers such as Tim Bresnan were suddenly gunning low 90s when in reality they're more like 82-86.
The toys clubs use are slightly different, and take in the full flight of the ball, which will produce proportionately slower results.
I don't bowl anymore, haven't in 16-17 years, so can only comment that in my county youth days I was probably mid-high 70s. Nowadays, its one over a season and pray that the ball gets to the batsman!