Alternators - Rectifier or Regulator. Most likely fail?

[Dr Doofenshmirtz]

The Alternator has gone on the wife's Clio, no charge, battery light on. The battery was very weak and I suspect it was putting a lot of strain on the alternator trying to charge it up. I have already bought another battery.

Option 1: Buy a new alternator costing around £75-£100
Option 2: Since the alternator is actually quite new (replaced in 2007) I'm tempted to rebuild it myself and save a bit of cash. I have the alternator on the bench and having inspected the windings, everything looks good.
A new rectifier is £11.20 and a Regulator/brush pack is £11.52 (the brushes on mine look fine btw)

What do you think is most likely to fail?
I can just buy both parts which including VAT and P&P comes to £35...but is one part much more likely to fail than the other?

The reason I'm trying to save some money is because I want to sell the car! Typical.

[Dr Doofenshmirtz]

If I put the battery on the charger it draws a lot of current, but never charges up enough to turn the engine over - so it may have been damaged?

[Dr Doofenshmirtz]

Thanks for the replies.

The battery was shot - £20 for a replacement from the scrap yard (Halfords 3 year maintenance free jobbie with a 2009 date stamp = result)

And also it was the regulator in the alternator that had gone. I guess the extra load trying to charge the battery blew it. £10 incl P&P from eBay. Certainly better than shelling out around £100 for a whole new alternator!

Definitely worth trying to repair things like this at component level.