Input data into HA from external PHP script

Hi all. I have a Nabu Casa account and am quite happy with that. However it seems I can get to a node red http endpoint using that and I really dont want to open up another port of my syste.

BUT I use a tracker in my car for other purposes and as far as I can find it doesnt have an API. BUT it does have a way of calling outside stuff using a a HTTP Get request. Its meant to be for SMS gateways but I am sure it will work

Its format is

SMS Gateway URL example: http://SMS_GATEWAY/sendsms.php?username=USER&password=PASSWORD&number=%NUMBER%&message=%MESSAGE%

and I can get lats, lons etc. Any suggestion on how I can get thoes numbers into HA? I really want to get them into Node-Red but not really suceeding on that front. Also looking into say using MQTT. All suggestions welcome