I think what you want is to set up a Tealium Generic Tag. Set the type to Script, put the src url into HTTP URL and then if you want to send a static parameter after the question mark, put the details into "Static Params" (In this example, you'd just put xxx_some_id)
However if you want to map dynamic variables to the tag, as long as you have the variables set up as a data source in the data layer, you can press Edit on Mapped Data Sources, select your data source (user_id, for example) and press "select destination"
You will receive a warning message saying "There is no toolbox available for this vendor" - just press Apply and then you can type in the destination.
I hope that makes sense.
Connecting data systems since the 1980s.