Do you have any paperwork with the key codes on ?
Some of the info is stored on the vehicles body computer.. but any locksmith would still need to cut a key blade to your lock profile and build a new key and chip
That's the way. On my long gone VW Caddy i had a similar problem although a duplicate key service produced a mechanical spare key before.
One fine day the original key refused to start the van, and i faced the fact that i didn't have a working key left. So i bought two fitting transponders, put them in the keys, towed the van to the garage, and let them join the new transponders with the van's computer.
Pricing in Euros:
blank key off the bay: 7
shaping: 7
programming: 45
My idea is getting a spare lock with at least one fitting key off a scrapyard, double the key, buy two new transponders, fit them in, and let the garage do the rest of the job.
There's a good chance to get out with less than 100 instead of 250.
Some side-story: When i've been last time on the island i haven't had two working keys yet. I travelled through your beautiful country usually spending the nights in my van. After finishing the driving for the day i usually took a few bottles of beer. In order to let the radio work i had to put a key in the lock. Being aware of police phantasy i put the key without transponder in.
In the night Police came up watching me drinking beer while i sat in the side door. They asked some questions, came up to me, saw the key in the lock and assumed drunk driving. I asked whether i may prove that i didn't, and they allowed me to take the gear out and to pull the hand-brake. Then i started with the effect that the engine died two seconds after having been started. I asked them to try to start themselves with the same effect.
After that they went apologising and wishing a nice journey. (These Welsh policemen were very polite which i appreciated very much btw.)
So, having a key without transponder at hand might not be the worst tip for life in general.