@lanikita 

How / Where can I purchase QuickBooks Mac Plus 2023? I would ideally prefer a version that is not subscription based and just need accounting features to keep costs down.

As of QB Desktop 2022, Intuit only offers the subscription license. Only scammers offer QB Desktop 2022-2024 with non subscription licenses. You should contact @Fiat Lux - ASIA for advise. You can purchase a new legit license of QB Desktop 2024 Pro Plus for single user = $650 + you can get $100 cashback. They will also share you another option to use QB Desktop with a non subscription license.