could this model helps?
https://gamemodels.ru/files/file/1555-ferrari-360-spider-gt-00/

Also, a 550 barchetta pinifarina would be perfect too
https://gamemodels.ru/files/file/1562-ferrari-550-barchetta-pininfarina-00/

Some of the vehicles are somewhat available as gta 5 vehicle mods,but not all of them.
If,by any chance,you are either a modder or knows someone that ports vehicles to gta 5,let them know if they are interested about it.

Addon is recommended,and if you want make it as a replace,don't worry, i can convert them into addons.

UPDATE:why the hell is there no 1998-2003 jaguar xkr coupe?
perhaps someone can make it happen,here's the model:
https://www.google.com/searchq=jaguar+xkr+coupe+2000+games&source=lnms&tbm=isch&sa=X&ved=0ahUKEwis-8z6p6PjAhUFxIUKHeJDBSEQ_AUIECgB&biw=1536&bih=706

just like need for speed 2,i'm a long time fan of the need for speed franchise, so i would like to see cars like this to drive in gta 5.
model:https://rmsothebys.com/en/auctions/MO18/Monterey/lots/r0146-2000-lotus-esprit-v8-se/699528