Arcadia is indeed the best brand of UVB - more importantly the T5 model. All Exo Terra's etc are T8 but also use old technology, I think even ArcadiaJohn on here says that no T8 (even Arcadia) is good enough to recreate the exposure they would get in the wild. So it's not personal preference, it's that Arcadia T5's are genuinely the best (plus you only have to change the bulb once a year which is a bonus!). You can have a nosey around their very helpful website > Arcadia Reptile : Arcadia Products Plc
< or Arcadiajohn on here yourself.
As the beardy you are getting is quite young, it's even more important that he gets the very best UVB - Arcadia T5 12% with reflector, going 2/3 - 3/4 the length of the tank is the best you can provide. It's easiest (and often cheapest) to order these online.
Heat bulb you can go with a standard household bulb, spot light or halogen (attached to a thermostat!). Watt depends on your setup - I would get a range of watts and test them all out (don't think you'll need 100W or above though).
If the red light and heat mat is for night time temperatures - don't bother. They require no heating at night at all, they can cope with it easily (and it's actually far better for them to be cooled at night)