I have come across 1/2p's, 1p's & 2p's in safely rolls for dates 1971 &
1979, so technically the must exist! (whether these are original or not though)
I've just done an Ebay search and i came up with this;
Try these links...
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&
item=3051246669&category=3397
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&
item=3051246746&category=538
Hope this accurately helps
Sylvester.