From the colour of the rollers and the mudguards I'd say it's a DeGraff trailer (LINK) so probably best to get the trailer serial number or the wheel size and ring them up (01276 855566). They are very helpful and will quickly tell you the bearing size. Buy one set from them (to say thanks for the help and support local boat business) and a spare set off ebay to stick in the car!
Eastern Thunder
Northern Exposure 5
