I am currently working on a project which involves a RF Amplifier. I found BC494 to be quite suitable for the same. Though, I am looking for its alternatives since I couldn't get one of these.
Use a website for checking your specific needs, e.g. the transistor 'filter' page on Mouser:
A search on internet:
2N3904 or 2N2222 might do you but a 2N3707 is identical to a BF494.
You pick a transistor to suit the circuit and specification requirements and, if you are lucky, there are alternatives that explicitly say in their data sheet that they are alternatives to the part you originally chose. Trying to compare "this" transistor versus "that" transistor by using data sheets alone is not going to produce an ideal match to your requirements or circuit (both unspecified). Successfully replacing a transistor requires detailed knowledge of the target design.
For RF, the Cob (feedback from collector to base, which affects stability-circles) is a key param. Also, for low noise, the rbb' needs your attention. And the package needs to be the same.
All this presumes the Ftau is also compatible.
For RF, you should use the S-params to evaluate.