I have a 1960 Freddie Grubb Track/Path bike. I am not sure which model or whether it is Holdsworth built.
However, It was recently resprayed and the re-finisher didn't seem to have any problem sourcing transfers.
It has circular badges to the head and seat tube . These both depict a 3/4 view of a cyclist with London SE20 below it (The postal code for his shop). The head badge is metal in 'releif a bit like the badge on my Hetchins. The down tube transfer reads Freddie Grubb in a pretty gold handwriting script (Mr Grubb's signature perhaps?)
If you have trouble getting transfers I can make some enquiries.
PS (in case you're interested.) It is built up with front and rear 24 spoke Campag Record large flange track hubs on Super Champion Arc en Ciel rims. It fact it is all Campag with a very handsome pair of steel Cinelli track bars and a badged stem.