Realistically, most of our Youth are probably promising enough for a call up. Roddy has potential to get a youth call up, but has somehow ducked under the radar.
Can't think of the Left Back you're on about, Carl Tremarco is brinking on his 40s, so I doubt Gareth Southgate will be looking to add him into the lineups, and hasn't been called up in the 16 years of his career to any level. McHattie I cast my doubts, as he hasn't made too many games and Cameron Harper could have a chance.
And Mckay, not sure if you're referring to Brad or accidentally mispelt Daniel's surname, but no, the Mckay (Brad) isn't looking likely for a scotland call up, however Daniel Mackay, has quite a fair chance, and likely will be in the Scotland squad in the forseeable future (assuming he's not linked with an irrefusable deal down south)