Mixed conditional? (simple past + will)

[SugarSpunSister]

Hello everyone! I would like to know whether the following phrase is possible. It's from a letter to a client:

If any further information were needed, we will contact you.

It sounded logical to me when I wrote it: it is very unlikely that it will be needed (thus the use of simple past, as in the second conditional) but, if that is the case, we will definitely contact you ("would" is not even a possibility here).
However, now I'm looking at it again and I've started having doubts about it. Should I write a plain first conditional just for the sake of grammar?

First conditional: If/should we need any futher information, we will contact you.

Of course, that one would be grammatical, but I really liked the first one better, since it conveyed the idea that we probably would not need to bother the client any more.

Thanks a lot in advance!

 

[pops91710]

Should any further information be needed, we will contact you.

Should any further information be needed, we will contact you. Sounds better to me.

 

[lingobingo]

If any further information were needed, we will contact you.
If any further information is needed, we will contact you.
If any further information were needed, we would contact you.

Or pops’s version.

 

[lentulax]

it is very unlikely that it will be needed

If you want to stress that this is very unlikely (for reasons, say, of diplomacy or courtesy - e.g. if they've sent you copious information and you don't want to suggest it's likely to be inadequate) you'll have to spell this out, e.g.' In the unlikely event of our needing more information , we will etc.'.