[NBwcs]

you should be able to pick a pump up for about £7 ( a little bit more as I can't see any Chinese sellers ! )

https://www.ebay.co.uk/itm/12V-90PSI-4-9L-Min-High-Pressure-Diaphragm-Self-Priming-Water-Pump-Caravan-Wash/313067820935?hash=item48e44bd787:g:ImAAAOSw3V1eqU6C


If you want wheels you can always buy a trolley for 15 quid and strap your back pack to it

https://www.ebay.co.uk/itm/Black-Folding-Boot-Cart-Shopping-Holiday-Trolley-Storage-Box-Crate-Foldable-25kg/352660667852?_trkparms=ispr%3D1&hash=item521c36bdcc:g:ysAAAOSwwStc1WR0&enc=AQAEAAACYIQvEcHUrT7nmUC3yY5qbPyaBN1nJEDYW8MyypsJPgXKV7I%2FQKOSwnBMfY2gwkiEAJ1av9h9Z%2FABi1tLqH9Viv8Uy%2BwBf1o4%2FWkJne%2B%2BvxpPBvBXcOFjefYqutf%2BhyMTg%2BBRM1oMOKIsXfBf8S0al7r%2B8v2fH7BjpNTrgJQforuNZrz2NL9e1%2FACiKAdkZ9pdqwnmxRQhGRsYK802twM260KGs31y97Him3Mcwvs7khXvacbMvGZmcWQ0Ky4LKVFQgqsWKsaVZMbAi0D8XQqv5m5AtlAC1x6H4yfyvfzmLk8WIrax1doXfQyPYtN0ua0R4Urfke5OU5WAJ6V9igK9fDkKt9ZjvqEDAuZASTepOGB3ZymwRCFRJX%2BroR8wH7GjcnaY5bXC9%2FJVzaTqD2%2FJOw9nOCdo049SqYDprBTwYOUj0sQ%2BD4iTVHSLzdTPbHjV9tFqs1FrDduvCVbcsaV1T8oDP1uV%2Bu%2FHtjwmFwjB6bwSw3x5r%2BIymvmGpFIzJjnnjj4TTdsAADoh11VTVwwvxRiJkLxSMtLa1MRc2%2B6alYXMbmqZc0O%2Fu%2FFz%2BCibez2k2k3yHvsI7OSIAlX1vIUcmGEyOC%2FQrh8eAtmG2pTb6qeKUO5KQRCWsodhLFiV0DxXDhQOXa3S6nVgsJgB%2BrVSm3EApaHTJyUfOYm5xugOjS94D%2BfyeHgbCiBNhUZM1lPrtJHsjCN6x59YwkBCuvY%2Bs4RznvoTwi%2BU%2Bgb6UeDnI5Vxy1KFAcMbvI0tDFAyxYkioonJ4kqjnxWoErAwbekMF0nMAzps1G%2BJ82TWxfwWR50&checksum=352660667852065a1a7f7fc14f90b076bec97fe59ec4

Thanks  for that Darren, found this which looks almost identical, has a picture of  what looks like the same backpack in one of the pics.
https://www.banggood.com/DC-12V-Mini-Micro-Diaphragm-Pump-Automatic-Switch-High-Pressure-Water-Self-Priming-Pump-p-1516588.html?gpla=1&gmcCountry=GB&currency=GBP&createTmp=1&utm_source=googleshopping&utm_medium=cpc_bgs&utm_content=lijing&utm_campaign=ssc-gb-tools-bf11-1107&gclid=EAIaIQobChMI4r7Gifzs6QIVh-7tCh0CEwaMEAQYBCABEgIUsfD_BwE&cur_warehouse=CN

[Smudger]

there's not a lot to choose between them, there is a bit of room should the sizes not be identical

Darran

[Suffolkcleaners]

Thanks Darran

Looks as though the backpack (may possibly) just slide into the crate and off away you go. They have a 25 and 35kg version. Anyone know how much a gardiners Backpack weighs full up? Cheers

[Smudger]

I thought the crate was for demo purposes 

basically its 1kg per litre of water and I would say a backpack itself would be around 5kg

Darran

[Suffolkcleaners]

I could be wrong but it looks like a foldable crate that goes into a trolley. Sounds like its worth a punt for £12.99 although I believe Gardiners backpacks hold 22 litres which would be 22kgs weight of water Plus around 5kgs like you say for backpack. Maybe the 35 kg one then. Will let you know how I get on 👍

[Mr B shine]

Have all the backpacks been bought now

 Has anyone a fresh link as I'm drawing a blank

[Smudger]

the best I can find just now

https://www.ebay.co.uk/itm/Electric-Knapsack-Pressure-Sprayer-Crops-Weed-Pest-Killer-Backpack-Chemical-Pump/333459593820?hash=item4da3bd9a5c:m:mKBcToltHm2j9en5bpHrI0w