Best way to deal with superseded parts?

We're looking for a way to take a product that has been replaced by a new version/SKU and have the new one show up when the user searches for an old one. For instance, SKU 1234 has been replaced with SKU 2345. If someone was to search for 1234, we want 2345 to show up. We're currently doing this on an older version of nopCommerce with a significant amount of custom code and tables and I'm hoping to simplify the process if possible.

I'm open to any suggestions, including "That's dumb, don't do that."

Hi, what nop version have you got? This can be done simply by adding the new sky column in the db and change the search procedure.
You don't need much code changes for it.

If you unpublish the old product, then "search for" for old SKU would not bring back anything.

Possible 'quick and dirty' workarounds would be to add "replaces SKU ...." in the product name, or maybe a product Tag

Another possible workaround:
https://www.nopcommerce.com/en/boards/topic/95881/301-redirects-for-products

I think we're going to go with the tags. We do a daily sync that brings updated products over from our ERP system and we can set that up to add the superseded part to the tag and then all we have to do is include tags in searches. This won't require any DB changes and only some minor code. I appreciate  the insights.