I have an older stanley general purpose backpack sprayer,It does not pump up anymore,Where can I get parts?

Something like this?

https://www.amazon.com/Winters-Economical-Pressure-Internals-Accuracy/dp/B0087UCJ6I/ref=sr_1_7?dchild=1&keywords=stanley+backpack+sprayer+pressure+gauge&qid=1633991257&sr=8-7

It looks like the sprayer is made by Chapin and badged to Stanley.

https://www.google.com/search?q=Stanley+Backpack+Professional+sprayer+61804+parts

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Chapin makes sprayers. They have parts. Just give model #. Phone 1-800-950-4458. Located in N Y STATE. Pump rebuild kit is $25.00 Inc shipping.

http://www.roundup.com/smg/gosite/RUP/help

I would like the answer yo that question

Drive out to the country side and look for a ACE or TrueValue hardware store. Bring your sprayer with you. They will likely have the right part for you in stock.

The picture looks a lot like a Solo sprayer I have. I wouldn't be surprised if Solo made them for Stanley. Do a search for Solo sprayers. They have a site. My sprayer is a Solo 425

the darker Seal has come off the plunger at the bottom of the unit , easy 5 min fix , just unscrew the allen keys at the bootonm take off the cover and remove the plunger , you'll see the plunger seal still inside you can fish it out with an allen key or similar tool clip it on again and reassemble

http://www.alamia.us/Solo_Sprayer_Parts_s/814.htm?gclid=CNvasPXY1ZsCFdVL5Qod3U4hJw

The handle on the right