I too was heartbroken and devastated. I quit color work for several years to savor my bitterness. And then I pulled my panties back on and started shooting negatives.
lol - i am at somewhat the same place; however, i absolutely refuse to give up on slide film... bitterness is a quite powerful motivator.
The world without cibachrome seems a duller place...
yep, definitely a duller place, particularly when you add in all the other great films, papers, etc that have also been lost. several of the options i have used:
1. there is still one lab in the US that i know of still printing cibachromes or at least was doing so somewhat recently:
the lab ciba. very expensive and someone else is having all the darkroom fun but you get a real ciba print. also, this is not a long term solution as materials will eventually run out.
2. as mentioned by others here, color negatives on ra4 paper. in addition to the kodak papers, you might also try fuji pearl and fuji super gloss. fwiw: i find the whites of the kodak metallic paper are too silver/grey - the fuju are pure white. for me the super gloss comes closest to a ciba print.
3. if you want to combine the best of both -- slide film and ra4 paper: scan your transparencies and have the files printed on the above mentioned ra4 papers. here, you get the color palette of slide film [which is the whole point, imo] and prints that are impactful in the same way as ciba prints. very inexpensive but again someone else is having the "darkroom" fun.
yeah, yeah - i know #3 is not 100% analogue and i really apologize for mentioning it in this venue... but, you are still using slide film [which really needs supporting] and color papers. heck, you can even rationalize this to yourself by thinking that the only thing really being replaced in a 100% analogue process is the enlarger... light in through film and out onto the paper, right !?
4. finally, as also mentioned above, go old-school and simply project the slides as originally intended. kodachrome was introduced in 1935 while the cibachrome process was not available until the early 1960s. last month, i introduced my college age kids to a night of projected slides. they actually put down their phones [after taking a picture of the event and posting it somewhere online to show how cool and hipster their dad was!]. they were completely blown away by this new-to-them way of viewing photographs -- it was the shared experience that was most eye opening. hey, sometimes you have to walk a long way to come back a short distance.