Amazon.com: JMBricklayer German Express Train Building Kit - RC Steam Train Building Block Toy, Scale Model Train with Train Tracks, Adult Engine Vehicle City Set, Gift Toys for Teens Age 14+/Adults(2348 Pieces) :
I upgraded my 7810 (40370) with a 4.5v motor and headlight : r/lego
Lego® 4.5V 12V TRAIN 7820 Mail Van Freight Post Wagon | eBay
LEGO 180 4.5V Train with 5 Wagons | BrickEconomy
4.5v Set identification - LEGO Train Tech - Eurobricks Forums
Vintage 4.5 V train from 1975. 98% complete. Nearly 50 years old and still works!!! : r/lego