Hey nja, nice machine! :)
Two things that would be pertinent to your question
#1 the grinder is generally considered to be more important than the machine when it comes to producing great espresso
#2 the Sunbeam is the absolute bare minimum grinder suitable for producing any kind of espresso.
The large adjustment steps (not to mention questionable build quality) of the Sunbeam mean that you wont be able to dial it in perfectly for your machine - I notice this even with my Sunbeam machine. There are users here who use the sunbeam machine but have spent as much or more than the cost of the machine on a better grinder!
Would be a shame to spend a lot on a great machine, then not get the most out of it to save a few hundred bucks IMO... Then again, since you already have the grinder you might be best off waiting until the machine has arrived, then having a play and see what you think. If your seller is nearby they may have a machine and grinder set up for you to compare results.
Alternatively, if youre in Victoria you could take advantage of Talk Coffees try-at-home offer: http://coffeesnobs.com.au/YaBB.pl?num=1206918643