There are a few multiclassing options that will grant you darkvision.
If you're willing to take 2 levels of Warlock, you can get the Devil's Sight Eldritch Invocation, which grants 120 feet of darkvision. It has the added bonus of penetrating magical darkness.
In Xanathar's Guide to Everything, the Gloom Stalker Ranger gains darkvision to a range of 60 feet. You'll need three levels of Ranger to choose the conclave. It comes with the added bonus that:
While in darkness, you are invisible to any creature that relies on darkvision to see you in that darkness.
As you mentioned, it would only take 1 level of Shadow Sorcerer to gain 120 feet of darkvision.
And some other options.
You already mentioned goggles of the night, an uncommon magic item that grants darkvision.
The robe of eyes is a rare magic item that grants darkvision to a range of 120 feet, among other benefits.
A belt of dwarvenkind is another rare magic item that grants 60 feet of darkvision.
If your party has a Wizard of the School of Transmutation, you might be able to ask them to lend you their Transmuter's Stone (6th level sub-class feature), which has the option of granting darkvision to a range of 60 feet. Alternatively, you could take 6 levels of Wizard yourself.
The 2nd level spell darkvision grants darkvision to a range of 60 feet for 8 hours. It's available to Druids, Rangers, Sorcerers and Wizards. You could either ask a party member of one of those classes to cast it on you, or take enough levels in one of those classes to be able to cast it on yourself.