Does anyone know how to import 4:3 DVCAM footage via SONY DSR 40?

Assuming you have iLink/FireWire on your computer, you can patch iLink from the Sony DSR40 and then use File > Capture... in Premiere Pro to capture your tapes.  The resutling files with be DV-NTSC 720-by-480 non-square pixels full frame (4:3) interlaced footage (480i60 or 576i50) requireing about 13GB per hour.  I don't recall if the Sony DSR40 had a widescreen mode, but it's possible for DV to widescreen with 16-by-9 squeezed into 4-by-3 instead of being full frame.

If your computer has Thunderbolt 1 or 2, you can use Apple's Thunderbolt 2 to FireWire800 adapter.  If your computer has Thunderbolt 3 or 4, you can use the Apple Thunderbolt 2 to FireWire800 adapter with the Apple Thunderbolt 3 to 2 adapter.

You might find an inexpensive FireWire PCI card if you have a tower with an available slot.

If your computer happens to be an M1 based Mac, you'll need to launch Premire Pro using Rosetta.

If you already have analog video input of some sort, you can always patch that instead of iLink, but that should be last resort.  Your goal should be a digital to digital transfer via FireWire - even if you have to go with a used Mac with a native FireWire prot to do it or a used Windows machine with native iLink port.