Can Infinity Kappa Polydomes be replaced by ...?

Can I replace my 3" Polydomes of my Infinity Kappa 7 with 2" Polydomes of Infinity RS-5 ? as they are so much easyer to find , and their frame is the same size as the original.

Has anybody tried it ? is there a diference in sound ?
Yoram, a telltale sign Polydomes are cactus is yellowing of the diaphragm, drying and cracking. I wouldn't recommend replacing the 3" Polydome midrange diaphragms in your Kappa 7's with the 2" Polydomes from the RS-5B as the power handling and dispersion pattern of the 2" Polydome will be different and may upset the balance/coherence of your speaker, and may result in the driver prematurely failing. You might be lucky and find an original Infinity diaphragm or driver on Ebay in good nic, but you don't know what you're getting and unfortunately Infinity's demise has given rise to a number of unscrupulous sellers selling often misrepresented or damaged parts at ridiculous prices.

Unfortunately replacement drivers (part #902-3075) have not been available for some time and Orange County Speaker Repair no longer have stock of replacement diaphragms (part #10-239), however they sell a generic replacement driver which is a drop in replacement (part #02-239) for around $130. My advice would be to have a look at their website. If you drill down into that part there are a number of user reviews which offer good advice about installing the drivers. Good luck and let us know how it goes!
Yes. There will be a difference in sound. Those are 2 totally different drivers. Stick to the OEM speakers.
I tried the replacement dome only that is listed on eBay. I don't have the equipment to install properly, and the midrange output on that speaker is 'off' from the original still in the other speaker. I don't recommend and of the other drivers, and I've given up - the search is on for replacements for my beloved Kappas.
English, it might be beneficial to Yoram and others who might read this thread if you could post a link, or clarify which Polydome replacement you tried and what specs were out? The reason I asked is that Orange County Speaker Repair, Simply Speakers & The Speaker Exchange all use and recommend the above-mentioned fabric dome replacement.