Alexander,
G'day,
Bottom line.... it's worth whatever your are prepared to pay for it. The radio's might be old but, if they're working alright that is all that really matters.
Yes, they could be expensive to replace but again, depends what you replace them with (second hand same unit's, TKM, reconditioned, or brand new / new installation, the outcome is again up to you and as such, so is the price. Hey..they could last you for years

, or they could die on your first flight as the new owner

- its a bit of a lottery in that regard, you could either be lucky or unlucky, but on face value not a deal breaker.
For me, my major area of concern would be more toward the the airframe and engine condition. Airframe corrosion or a crappy engine is likely to more a deal breaker than a couple of doggy radios
As far as a supposed "good deal" goes......the price mentioned is of course the "asking price" - not necessarily the purchase price, so if the aircraft interests you, you'll need to go the next step, do some
real research on the plane(airframe and engine as mentioned above) and if your still interested at this point...some bargaining. I should mention, a couple of snags can be a good thing for price reductions, just be sure you know you stuff, cause you can easily get burned trying to get a bargain basement deal at this level). Only then you will know if it's a good, and proper price. We can sit here and and offer all sort of theories on it which at the end of the day are really only personal preferences, but, and more importantly.....what's it worth to you...
Good luck with your search