Q&A: Help Finding a Round Diamond around 0.8 Ct. for a White Gold Ring with Around $3k Total Budget

Hi there! I stumbled upon your website and have learned so much. The knowledge I have gathered has allowed me to drop my budget on the ring and get it sooner so that I can propose. I have a couple of questions. First off, I have selected a ring from jamesallen.com and would love to know the approximate carat size shown in the ring in their images if possible. This is the ring I have selected.
https://www.jamesallen.com/engagement-rings/solitaire/18k-white-gold-diamond-studded-bezel-solitaire-item-7849?a_aid=dmnd1357

Also I would love help selecting an appropriate diamond for this ring. Originally my budget was around $3000, but it will still be months before I would reach that goal. I am wanting something similar to what is shown in the images of the ring, unless of course that puts it around 1 carat. I originally had priced the ring I believe with an SI1, Colour J round 0.8 carat diamond for around $3000. What is the best diamond you think I could get for around $2000-2500 with this ring?

Thank you in advance for your help! 

 Thank you for the response. I have absolutely no problem giving you credit for the advice at all and will be using this email address to make the purchase.

While the diamond you have selected does look perfect, I am trying to keep the total purchase price of the ring below $3000. The setting I have selected is $900 so I am looking for a loose diamond under $2000. Sorry if that was not clear.
Are you able to tell me what carat size is probably displayed in the images of the setting? I want something impressive for my budget that wont look too small. 

What do you think of this diamond compared to the one you had sent previously. This one has a medium blue fluorescence which you recommend on your site if buying a diamond with a color of H or lower.
https://www.jamesallen.com/loose-diamonds/round-cut/0.70-carat-j-color-si1-clarity-excellent-cut-sku-288276?a_aid=dmnd1357

Here is the one you had previously recommended.
https://www.jamesallen.com/loose-diamonds/round-cut/0.70-carat-j-color-si1-clarity-excellent-cut-sku-271808?a_aid=dmnd1357

Thanks! 

Ok, I looked up about the tables.
In regards to these two diamonds however, my concern is that there are many more flaws visible in the enlarged 40X image for the first one that you sent. I know the diamond will never be that seen that close up, but are all these white wavy strands completely invisible to the naked eye?
You are of course the expert, so aside from the table size, is there anything else about your recommendation that makes it stand out over my selection?

Thanks.