Hi Ally13. I concur that the Celestron with the steel tripod looks the most solid of the 3 70mm scopes (although there is a fair bit of plastic in the mount head...). I am not sure you need the extra eyepiece just yet: it comes with a 10mm and a 20 mm (90x and 45x respectively). I would practice with those first if I were you- it wont be easy keeping things in the field of view at 90x, let alone 120x with a 7 or 8mm eyepiece.
Later you might want a lower power eyepiece for terrestrial use (say a 30mm?). In any case, Andrews (
http://www.andrewscom.com.au/site-section-10.htm - go the the "Guan Sheng" section and scroll down) have GSO "super-plossls" for $39: they are pretty good value, or Bintel (
http://www.bintel.com.au/Eyepieces-a...6/catmenu.aspx) have their own brand plossls for $49
- so if you want to go down that route they aren't a bad place to start.
You could also try Matthew Lovell at
http://www.telescopes-astronomy.com.au/ (best to ring him, he is pretty helpful and his site isn't the easiest to navigate! However he has very competitive prices, and he can get things in for you too.)
Oh and I agree that the 50mm scope is
not a good idea!
All the best,
Dean