You could try the 'old banger' approach. If you have somewhere to store it, buy a second one on ebay (probably dirt cheap nowadays) and keep it handy to rob for parts when the time comes. This probably works less well for ovens (not much to go wrong and most likely to be the element each time) as it does for, say, washing machines (lots of parts).
This can come especially handy for builtin appliances, where the alternative is rebuilding the kitchen to match the cutouts of a replacement, which always seem to be in a different place.
Theo