Just be careful with the round one, it is only a paint scraper blade.
Proper blades can be purchased and will fit, if you need a longer screw to fit them I have some in shed.
Have a lot of fun and many thanks for bidding and winning them, your payment has gone to a good cause.
I had a friend around tonight who wanted to make a cover for his old bell with tubes as the original was yellow plastic so didn't get to play with either the round or square grump today.