The card keepers are most commonly seen in green and yellow but I have seen pictures of keepers in an all black strip. The only one I have appears black but when scanned is clearly a black over-printing on a green shirt. I will put a copy on the sundries gallery. Are all the black keepers like this? It is not obvious to the nakes eye but only shows up when scanned. The gallery picture looks strange around the neck but this is a photograph not a scan.
The keeper figure may originally have been intended just for show as the base was designed as a block to bat away the ball. The early assembly outfits describe them as T Bases but are not specific about whether the block is made of wood or plastic. If anyone has the genuine article I would be pleased to know. As with so much of the early sets, within weeks flat plastic keeper bases were made available as an accessory but the T Bases remained in the second set: more accessory sales no doubt followed. The exposure of the card keeper to bending at the ankles in the flat base was immediately obvious and limiting.
There are early keeper bases in yellow and green in the brittle base type but I have not seen any black ones yet. As with other bases there are large smooth-topped keeper bases before the common types. Although an improvement over the card ones (the celluloid keepers remained undamaged for longer) they had some odd characteristics in play. The ball could still 'go through' a celluloid keeper, but sometimes the goalie bounces the ball back up the field, turning defence in to attack. The celluloid keepers also had a habit of losing their head, literally.
Rather than show a picture of a celluloid keeper here I think a gallery page is justified. The keepers had long sleeves, unlike the outfield players and other colours started to appear. On the official lists grey and crimson keepers appeared as accessory HH although which teams they are supposed to be for is a little mystifying. Keepers also appear in white shirts but these seem to be only in the Late Celluloid type in bags. Whether or not this means there are genuine later teams with more than one keeper type/colour I am unsure.
A further set of accessory keepers appeared in 1956 (thanks Ashley for correcting the date) in a kicking pose. They are rather strange and completely different to all other flat subbuteo keepers, but printed on the same player shape. Possibly the more active pose was intended to compete with those of the Newfooty players but they were issued in isolation with no matching outfield players. Some people may have used them to take goal kicks and then remove them from the field of play which is the only sensible use I can come up with. Using a defender was always an annoying unbalancing of the defence. These keepers do not appear to have been intended to be used in play as the set I bought in a bag comes with matching white and royal blue bases without a hole for the wire.
Flick Me! subbuteo archive goal keepers