Poor man's T-track

[D.C.]

I was intending to fit some t-tracks/t-slots whatever you call them to my machine but they all seem horribly expensive.

The cheapest I've found is alu ones from axminster here:

Buy Axminster Universal T- Track from Axminster, fast delivery for the UK

But that costs about £8 a metre.

Is there any reason why two pieces of steel angle welded to the frame like this spanning the width of the frame wouldn't do just as good a job for 1/3 price?

Surely this would also give the added benefit of a bit of extra bracing to the frame aswell. Is there a 'standard width' for t-slot tracks so that any fancy attachments I might buy in the future will fit?