worth selling 125 sm

hi hope someone could shed some light on what these bikes are worth, I'm looking for selling mine in the near future, and unsure of what price region i should be looking at.
its a 2003 model with a few extras such as
renthal handle bars £50
brand new bridgestone battlax tyres £160
newish chain and sprockets (fitted within last 6 month)
it has done 8000 miles on a 2008 year engine ( fitted within last 12 month )

hope i have given enough information, as im looking forward to selling my bike now that i have passed my test
thanks for all your input in advance
its a 2003 model with a few extras such as
renthal handle bars £50
brand new bridgestone battlax tyres £160
newish chain and sprockets (fitted within last 6 month)
it has done 8000 miles on a 2008 year engine ( fitted within last 12 month )
hope i have given enough information, as im looking forward to selling my bike now that i have passed my test

thanks for all your input in advance