There is some decent diving on the coast, in Spain the Medas Islands are popular and you will hopefully find stuff open that time of year (
La Sirena Diving Center - Diving center - La Sirena) In France it is also getting late in the season and you would need to go some distance east I would think. There is good wreck diving round Marseille which is generally in the "tech" category.
Epaves | PLONGEE TEK MARSEILLE
You need a recent medical to dive in France and they will look for a CMAS recognised certification. CMAS 3 star is the key to everything. Some of the IANTD certifications have recently gained CMAS recognition but I am not totally up to date on the Trimix ones. IANTD Adv Nitrox is certainly CMAS recognised. French dive centres tend to be very poor at email so phone is the better option to check details and dive availability.
The weather is going to be your main issue. As above the Lot caves are very much worth a visit and Oli is a good start point. He is a good friend of mine and he speaks good English although he is Belgian. It is a very friendly dive scene and very international there. If there is heavy rain the caves will not be accessible, the flow is too much and the visibility destroyed. Just enjoy the fantastic scenery and wonderful local food and wine. There are lots of dry show caves if you like that sort of thing.
There are good caves in Spain too but I think the logistics would be harder than the French ones. From Málaga it is a very long drive to France. Another venue you might look at is Gibraltar although the diving is very much of the recreational variety at least everyone speaks English and will respond to email. I guess it depends on how much time you have to spare. Do also consider the Balearic islands - although that is a short internal flight to get to them they are warm and great fun even at that time of year. There is good diving if you look hard and sea caves there too. Get a flavour of things here -
Dives – Scuba Ibiza
If you are up for a short flight there is also Sardinia.
Protec Sardinia - Europes premier Technical cave diver training facility this will be less weather sensitive and has all the tec and cave you could want. Of course this is not the low cost option but you need to factor in the 8-10 hour drive and the motorway tolls so the rental car isn't a cheap option either. Diesel is much cheaper than gas so try to rent something that is diesel if you do have a drive round. Also the mountains are in the way of a direct route to the French caves and you need to think about logistics of that.
If you need more help with the caves or France please post up some more details of where you would like to go and how long you might stay and I'll do my best.
edit - this might be of interest as well
Local Cave Dive Sites @ Rec2TecDiving Not so far to go and with some good looking cave diving.