Try Model Spares Burnley (they now have a proper website) Abbiegails, again on the web or Call East Kent Models on 01227 770777 any of these people should be able to help, while you are at it get some spare brushes as well so that you can clean the armature, replace the brushes and springs and adjust the brush arms for the best pressure (it's called tuning) and your HST will be off like a startled gazelle!
Do you have any old Mainline wagons or rolling stock? The couplings on these are spring loaded, and the springs, easily removed, are the exact size for motor brushes. I have used several, and the wagon couplings still operate easily without the spring.
A forum community dedicated to Model train and railway owners and enthusiasts. Come join the discussion about collections, displays, models, styles, scales, motors, reviews, accessories, classifieds, and more!