Hi InsO. Unfortunately no direct Showmasters people read this forum any more so your only option is to keep sending emails I'm afraid. I'd say send an email every week until you get your items back, because the service is just not acceptable. Anything they say about volunteers is just lousy excuse making - they're not a flipping charity shop.
They have your stuff! They have plenty of other people's stuff! It can't be that hard to send things out!
Exclamation mark!