On eBay make sure you have Location / Worldwide checked on, and auctions only tab selected on top and then search under the stamps category for 'gb kilo*' and you will get 45 or so results.
http://www.ebay.com/sch/Stamps-/260...3286.c0.m283Searching for 'gb on paper' will give you some of the same but also some different ones.
Do not go so deep into the categories that you stop some results coming up. Just stay in the upper general category of Stamps and search for different word combinations from there.
Try with UK substituted for GB also of course.
Search for 'grams' is sometimes helpful also but some people like to abbreviate even the short word gram to grm or gmm or gm. You never know. You just hope they also included some of the orher words you are searching for.
You can go into the categories and look there but sometimes people put things in the wrong categories when they are listing more than one item that night or chosse the incorrect category to start with. The categories in Europe and different than in the USA too.
Example US stamps
Stamps - North America - United States
Stamps - United States
This doesn't help in finding things at all so you are left with searching for words or numbers or just cruising through all the stamps listings which is interesting but very time consuming.
Searching for Us stamps is a special challenge. Search for the always there (hopefully) word 'kilo*' (the asterick being a wild card so the search returns anything with the letters kilo at the beginning) but then also do separate searches at times for 'on paper' or oz, lb, lbs, pounds, ounces, grams, gms, US, USA, United States, "U.S.A."including quotes as some people think that the eBay search program understands periods (which it doesn't), "U.S.A" because some forget the last period, (sometimes no country name or abbreviation at all as sellers have the idea that it helps economies to not sell to other countries (not correct, never was, never will be)), North America, the French words for any of these, German, Spanish, etc.
Sometimes, from Europe, you will get United States mixed in with Canada as it is all the same to some people there. Or a world or worldwide mix that has mostly North America stamps. I'd rather get one countru I wanted but sometimes you have to take what you can get.
Remember to search for 'off paper' and the same in other languages, as those mixtures are interesting also. It's all good.
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Use different words like mix, mixture, mix*, lot, collection, assortment, selection, page, bag, box, scan*, scanner, pile, etc, etc.
It is fun searching for weird (seemingly) combinations or words and mis-spelled words and odd lots as a lot of people will miss these and the bidding will be less ferocious as only the searchers will find these and most of them will want a bargain so they can resell the lot for a higher price.