anything is better then the JJ's. JJ's are a reliable new production tube that are not bad just not great.
gold lion kt77's are a replacment in most amps for EL34's but they are not a EL34 sonding tube more modern and detailed sounding but less warmth (more similar to kt88's). they also take forever to break in.
NOS tube wil be your best bet but are also much more expemcive. lots to chose from and way too many to list here. google is your friend look for tube shootouts.