New hot water tank time

[ReconMarine]

Our Jayco 31 BHS sprang a leak last week, hot water tank went kaput. I spoke with a dealer and was told I could replace the tank not the entire unit.
Took tank out today and have a couple questions:

Does a new tank have the heating element or do I need to purchase separately?
Electrical panel seems fine so a tank replacement should be okay. Pricing of the Atwood unit is alcove the place, $927 from dealer and less that $400 online through Amazon.
Tank only is $280 from dealer and $145, again from Amazon.
Both are genuine Atwood parts and I'm wondering about the huge difference.
I get dealer markup and profit margin but wow.
Anyone here have recommendations?
Thanks,
Nick

[Robbbyr]

In my prior RV I replaced just the tank, it also was an Atwood. The job was fairly simple and the instructions that came with the tank were simple and accurate. I did buy a tank with an electric element, I have heard it can be very difficult to remove the existing element if the tank has been in service for some time. I didn't feel it was worth the hassle, and I figured I might damage it anyway!

I got my replacement from Ebay, it was a genuine Atwood part and was significantly less than what my local dealer wanted. Even with shipping I saved quite a bit.