That looks very like the UK Post Office tool I mentioned. Take a look here :
http://www.samhallas.co.uk/collection/test.htm
at the 'Extractor, Lamp, No 5'.
This tool has an extension moulded on the handle with a concave end to push the
replacement lamp home. It was originally desiged for those side-contact lamps
used on telephone switchboards (the UK ones are much longer than the US ones,
BTW) but it is very useful for other lamps.
Don't ask me where to get one. I found mine in a box of oddments at a telephone
enthusiasts swapmeet over here..
-tony