Re: need a gps/fishfinder mk or eagle
Walmart may have it but Humminbird has discontinued it therefore warranty claims could be an issue if needed.
New with receipt from dealer and HB will honor warrantee. If they had to replace it and they did not have that particular model, they would probably give you a free upgrade to the current model with same or better capabilities. I'd expect it is the same at Lowrance/Eagle. FWIW, I haven't seen any mfg stiff anyone on a discontinued model.
Now, if you bought a 5-6 year old model, new in box, from someone on Ebay, that might not be covered. Technically, their website indicates that even if it is new model, never opened, and resold, it is not covered. I have heard of cases where they have, though.
A Walmart receipt is not going to be any issue.