I need to sterilize a glass container for making spore syringes (small beaker or a Petri dish) without using a pressure cooker.

My oven has thermostat and is able to heat up to 250 C (450 F). Could the oven be used for sterilization?

I am aware the oven itself is not a perfect environment though, so I plan this procedure:

1) wipe the glassware and pyrex dish (on which the glassware will sit) with 90% IPA
2) let it completely oven dry at low heat (e.g. 80 C / 176 F)
3) close the Petri dishes without touching them (using IPA-wiped metal tong)
4) crank up the temperature to 180 C / 356 F for 30 minutes or so; now the glassware is dry so no condensation should happen and the contams should get incinerated
5) let it cool, maybe under some cover

Now since the Petri dishes are closed I guess not much contaminants can get in. I would wipe the outside surface of the dishes with IPA again before putting them in the glove box.

Is this procedure sufficiently sterile?

I had success with just boiling the glassware and then wiping it with IPA. The resulting spore water has been clean enough so no contam outbreak happenned. But I know some molds can survive boiling and alcohols hence the idea of using oven.

Please don't advice me to use PC. I plan to purchase a PC but I want a big one to use not only for sterilization but also for big jars and these PCs are super expensive (10L one costs over ~400 USD in Europe and does not even have a gauge - I would have to order All American some time in the future).
Everything I use is sterile (the syringes are pre-sterilised, the water is a sterile Water For Injections in plastic vials) - the only problem it the glassware.

Bruh where are you shopping
They arent that expensive. Here another one
Yes its true that they are sometimes blown way out of proportion like WMF brand ones for like 300.
There are small dirt cheap ones tho. You can buy like 5 of them

Whith the glass is okay. But i would blast the metal tong with a torch.
Also just fill like 70%IPA or alcohol into a bottle and just spray everything that comes near/in contact.
Dont forget 99% is inferior in germ killing.

Also closed petri dishes contam easily you need to wrap em in luminium foil that you sterilise with em to make em even more secure.

Thanks Ulim, that items go to my bookmarks now.

I never searched specifically for an autoclave as the lab equipment is usually super expensive - but you proved me wrong.

I don't like the small PCs because I really want to sterilize at least 4 big jars at a time. Also it is often hard to find whether they make it to 15 psi - the electric ones for example fall short and the cheap ones don't have detailed specs to find out.

Yes I use 70-90% IPA, not 99%. I read 70% is the best but it leaves some water behind.

Okay I will flame sterilize the tongs (I don't have torch but an alcohol lamp) ... and cover the dishes in alu foil.