As always, NR gives you lots of ways to do things. Possibly the most simple, using only core nodes, would be something like this.
[{"id":"c4310b2a.540fb8","type":"inject","z":"bef81aa8.c22888","name":"","topic":"","payload":"75","payloadType":"str","repeat":"","crontab":"","once":false,"onceDelay":0.1,"x":150,"y":120,"wires":[["e656e38f.c43398"]]},{"id":"e656e38f.c43398","type":"change","z":"bef81aa8.c22888","name":"","rules":[{"t":"set","p":"payload","pt":"msg","to":"payload & ' ' & $now()","tot":"jsonata"}],"action":"","property":"","from":"","to":"","reg":false,"x":300,"y":120,"wires":[["43cb85be.b7a08c"]]},{"id":"43cb85be.b7a08c","type":"debug","z":"bef81aa8.c22888","name":"","active":true,"tosidebar":true,"console":false,"tostatus":false,"complete":"false","x":470,"y":120,"wires":[]}]
If you are not happy with the date format given by the JSONata $now function, you will have to do a bit more work.
