Bock is a lager but not all bocks are black.
The dark lager at the Lowenbrau is a Dunkel, not a schwartzbier nor a bock for that matter. Is this correct?
http://www.lowenbrau.com.au/beers.htm
In which case, please forget my previous post. This beer would be even harder to replicate with kits and extracts. I am having a strong aversion to lagers made from extracts recently. At the very least you will need to reduce body in the beer with highly fermentable content such as sugar but this has a poor effect on head retension and malt flavour, which is what makes this style. At the very least perform a mini mash. I have not tested this recipe, but would humbly assume that this may get close to a Munich Dunkel:
1x Coopers Bavarian Lager kit
1Kg Light Dry Malt extract (Or 1.2Kg Light Liquid Malt Extract)
1Kg (*) Munich Malt
200g melanoidin malt
15g Hallertau hops
Mash the crushed grains or steep in 2.5L of water at 65°C for 1 hour then strain water into pot. Run the runoff thru the water once more for clarity then rinse thru with another 2 liters. Bring liquid to boil and boil for 5 minutes, add hops and extract then boil 10 minutes more. Put lid on and chill the pot for one hour in sink of cold water and ice, add to fermenter with kit and use the Lager yeast supplied with the Coopers kit or pitch the lager yeast you prefer. Ferment at 12°C or lower until finished, perform diecetyl rest before FG is reached, then lager at 1°C for 1 month before bottling or kegging.
(*)Depending on the colour of the extract, you will need a mixture of light and dark Munich malt. I would be inclined to make extract light and Munich dark.
This beer is not easy to replicate without the grain as Munich Dunkel is a malt driven beer. It is also not possible to come close without brewing with lager yeast at lager temperatures then a lagering of at least 2 weeks.
I do not wish to rain on your parade, but you cannot make a silk purse from a sow's ear. Pardon the mixing of metaphors, it is late.
