Thanks all- Tiermann (I would never have got that they were cycle stands- no part number in PlaymoDB, no pictures!), Playmofire, Rasputin, flatcat and Tim_W. Part 5 is definitely PM (PM mold numbers are distinctive, no?), but the others which no-one could identify (9, 10, 13, 16, 17, 18) probably aren't PM.
I have some more mystery bits somewhere, so I may ask for your help again. Thanks very much!
Graham