My rival crockpot has craze lines in the bottom. Is it safe to use it?

Rival are a Crock-Pot copy / clone. You may find the corresponding Crock Pot size, or buy one from Amazon based on the diameter.

https://www.amazon.com/replacement-lid-rival-crockpot/s?k=replacement+lid+for+rival+crockpot

https://www.google.com/search?q=Rival+Crock+Pot+model+50301+replacement+lid

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Question edited for clarity.
Question moved to maker model category.

No one has documented the disassembly of yours, but there is this one.
https://www.ifixit.com/Guide/Rival+Crock+Pot+3120+Disassembly/153471

https://www.google.com/search?q=Rival+Crockpot+3656+remove+base

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Here's a PDF with a copy of old Rival Crock Pot manual. Page 8 discusses recipe help for the 2 Quart model. http://www.megaheart.com/pdf/crockpot-cookbook.pdf

Go to www.crockpot.com. This is the Rival Crockpot/slow cooker site. Scroll down and enter the model number in the appropriate space. The website will search, show you the crockpot, and give you the order number and price of replacement parts.

Sadly, these units are built for low end use and replacement parts are rarely available. Try shopping your local thrift shops for something close, although whatever you buy, make sure it is heat safe.

Check your local Goodwill or Salvation Army stores -- crockpots, liners, and lids show up their pretty often, and are usually very reasonable.

For what it's worth, when the handle on my mother-in-law's crockpot broke, I went to Home Depot and bought a cheap wooden drawer knob (about $1 as I recall). I put a plastic washer between the knob and the glass and another under the screw head from the bottom (to prevent cracking the lid), tightened the screw and good as new.

Try one of the following sellers:

To contact the manufacturer, try calling 800 #. 1-800-323-9519 (US number) for replacement parts or try www.crockpot.com

Rival Crock Pot Replacement Parts from MarBeck.com

Crock Pot Replacement Parts | Slow Cooker ...

www.rivalproducts.com
good luck

I have a new Rival crock pot, I got for a christmas gift, after using it only about 4 times it does not heat. How do I get warrenty? It was a christmas gift and I have tried Zellers and Home hardware, they do not seem to carry this certain model, it is a "Smart Pot" Rival Crock-pot , Where do I go for help?