What headset bearings do i need?

[TheFungle]

I bought myself a £20 Trek 4300 for cycling around the RAF camp I work on, it's in good Mick apart from the headset which clearly needs new bearings.

I'm I being thick or is it missing a bottom bearing?

[Benmac]

Certainly looks like there are no bearings in the bottom. The race looks like there should be loose ones in there. Considering how crusty it looks I'd maybe just buy a cheap new headset and whack that on. OK, it's 50% of the price of the bike but you can get perfectly decent Chinese cheapies on ebay for a tenner.