sorry I edited while you were replying…
in that case – as above look for the range of tyre sizes in the manual – look at narrower contact patches, not necessarily the smallest dia rim, then look for rims to suit that tyre size.
You’ll probably find second hand sets of wheels for your model in those smaller sizes as you’re driving on the wheels size most people would swap up to. Alloys are so ubiquitous now that they’ll possibly be cheaper than new steels.
Theres a site that sells aftermarket steel wheels categorised by make and model. I can’t remember which on just now – but I was looking recently as my GF wants to ditch alloys all together and have some wheels that can actually hold air.