What are the coins good for?

It's Saffron money, who knows what they're worth. But maybe it's not their purchasing power you care about at this moment.

The message says something about "Shuffle". What does it remind you of.

A shuffleboard?

Examine the shuffleboard and its grid of numbers. Its configuration looks so much like... a keypad?

Note the locations of the numbers seen on the coins (1983) on the shuffleboard.

Go to the bridge door keypad, and tap the combination corresponding to the numbers 1-9-8-3 as they were on the shuffleboard.

Tap 2-8-3-6 on the door keypad to unlock the door.